The present invention relates to the application of glue to closure stamps for insertion onto packages such as cigarette packs.
The packaging of cigarettes is performed mechanically by means of machines which sequentially deposit tobacco onto sheets of cigarette paper, roll the sheets into cigarette form, insert the cigarettes into a package, seal the package, and apply closure stamps to the package. Machines of this type are manufactured, for example, by G.D. Societa per Azioni, Italy.
In that machine, the glue is applied to each closure stamp by two thin rotary wheels. As the wheels are rotated about a common axis, the outer edges of the wheels pick up glue from the glue pot and then apply the glue to the stamp. Hence, there are formed on the back of the stamp two spaced-apart, parallel lines of glue which extend from a leading edge of the stamp to a trailing edge thereof.
When the stamp is applied to a package, there is a tendency for some of the glue to emerge from the edges of the stamp, and thereby mar the appearance of the package. Mechanisms have been proposed for alleviating that problem, e.g., by spacing the ends of each glue line from the respective edges of the stamp. For example, a glue-applying wheel is provided along its outer edge with a plurality of circumferentially spaced, axially extending grooves. Each groove forms a pocket that picks-up glue from a glue source as the wheel rotates. A scraper engages the peripheral edge of the wheel to scrape off all glue except the glue situated in the pockets. The wheel continues to rotate, whereupon the pockets come into contact with a stamp in order to transfer daubs of glue from the pockets to the stamp. The pockets occupy a circumferential portion of the wheel edge sufficient to ensure that the ends of the glue lines are spaced from the respective leading and trailing edges of the stamp. There exists a risk, however, of the glue becoming dried in the pockets, thereby inhibiting a proper depositing of glue on the stamp.
It would be desirable to minimize that risk while ensuring that the glue lines are spaced from the stamp edges by means of relatively simple modifications to a conventional glue-applying mechanism.